ORACLE的(+)用法

（+）相当于笛卡尔积

SQL> select * from BBED;

ID NAME
---------- ------------------------------
1 zhaoxu
1 kingle

select a.*,b.*
from BBED a,BBED b
where a.id=b.id(+);
ID NAME ID NAME
---------- ------------------------------ ---------- ------------------------------
1 kingle 1 zhaoxu
1 zhaoxu 1 zhaoxu
1 kingle 1 kingle
1 zhaoxu 1 kingle